15 MSH missing in lower cycilinder

[boscoe99]

Go to the top of this page. This is what you will see.

[99yam40]

I found the blue horizontal bar but it was on the home page. I copied the part number into SEARCH and got the following:

This Yamaha 63V-11181-A2-00 GASKET, CYLINDER HEA is used on these models and components:

2006 and Later 15MSH CYLINDER CRANKCASE
2006 and Later 15MSH REPAIR KIT 1
2006 and Later 9.9MSH CYLINDER CRANKCASE
2006 and Later 9.9MSH REPAIR KIT 1

Is that right? Its says Crankcase....

I need to get it right the first time. If I have to reorder the gasket because I was sent the wrong one, I'll be stuck without my outboard for about three weeks. I don't have that much beer on board the sailboat

Appreciate a bit of reassurance here. Thanks...
Bry

Yes that should be the right gasket.

Those are the pages that this part # can be found on , they are links to those pages . if you click on them on the page you found them, it should take you to the page in parts system

[yammie15]

Boy, this site is a bear when it comes to finding anything to buy. I want to support the site because you guys in the forum have been great. But I just spent an hour trying to locate a service manual for my 15MSH, 2007...
I'm not a computer geek, but this site is wearing me down.

Anyone... smarter than me... what's the part number of the service manual?

Thank you...
Bry

[chummy70]

YAMAHA MANUAL STORE

[yammie15]

Thanx chummy.... Got It!
Bry

[99yam40]

Hopefully you found the Yamaha manual number you were looking for.This is what I saw when I looked it up LIT-18616-02-59.

you can do a web search for it and might find a down loadable one, but not sure if it would be a Yamaha manual or not

[TownsendsFJR1300]

And here the link for you part, its states "Gasket, cylinder head", you have the correct part #:

63V-11181-A2-00 GASKET, CYLINDER HEA

[yammie15]

Thank you everyone. Just putting a order together.
Bry

[zenoahphobic]

ok
a small logic quiz.
to steam clean a plug we need water and heat, lots of heat as it must go over 212*F.

if water is in the combustion chamber how to we get heat?

see why its a unicorn?

unlike the internet myth of steam cleaning plugs, water will cause a black to brown crust to form on the plug.

as water prevents combustion there is not enough heat to flash into steam.

kinda like putting tin foil balls in the hub caps will fool a radar gun.
that one has been around a few years before the internet.

I've been on holidays, didn't see any unicorns , as you like to put I guess the theory behind what a spark plug should look like.
Water doesn't have to turn to steam for it to be a cleanser, just hot.
You say water needs to be 212 degrees to turn to steam.
Peak temperatures inside a combustion chamber can be 4000 degrees so there is plenty of heat in there to make it go to 212. Even closed systems use water heated far greater than this to cool an engine.
You say water doesn't burn or infer it puts out the fire in the combustion chamber. In small quantities this is simply not true.
Remember the OP says that that cylinder was still firing, not simply a slave driven by the good cylinder.
I might also add that products produced by combustion such as CO2 and Sulphur dioxide turn into very acidic substances that also eat and clean out the combustion chamber.
So I am still of the view that exhaust sludge is getting in there. Not denying some water but the problem looks greater than this. Just water would leave the firing plug cleaner. How different should as saltwater wet plug should look? seeing you said it should look different, but the OP said it is run in saltwater.
I'm sure there are many that like to get to the bottom of this very very fouled plug.

[rodbolt17]

just because a cyl can spark doesn't mean the fuel/oil mix is burning.
does not take much water in a two stoke cyl to put out the fire.
I have been doing this over 30 years now.
I have probably seen more water in a cyl on two stokes than the next ten posters here.
I have NEVER seen a two stroke plug steam cleaned cause it simply cannot happen.
you can see a dark brown to black crust form.
in saltwater you may also see small green flecks appear on the center electrode.
but typically if the plug comes out a clean white its fuel washed due to way over rich or the fuel is not being burned.
old myths die hard,esp internet myths.

and yes I am fully aware of a water injection system used by Chrysler back in the 60's. yes I have serviced that water injection system.
yes I have been doing this a long time.
yes on a large displacement 4 stroke AND a carefully con*****ed water injection you can get a bit of HP and a bit of knock retard.
not on a two stroke.

[zenoahphobic]

Thanks for the more information.
I cannot categorically state that I have seen water cleaning a two stroke, except some that have ran before submerging, the model boat being retrieved with the small engine full of water. Those that did not self destruct and ran again after drying out distinctly had cleaner head. Is this the same as running with water maybe not. Yes con*****ing anything going into a two stroke is far more fickle than a four stroke. I have seen many Fourstroke car engines cleaner after water leaks. Sometimes the owner knows more about the running of their engines than any professional, oftentimes does not get much info or even bull.
I have a healthy curiosity in my engines and have not got any "steam cleaning" myths or not off the web.
I have also seen plugs foul sludgy where two strokes without water cooling when the exhaust manifold has become loose or leaks or something is amiss ( e,g. two stroke exhaust timing valves ).
Maybe my two stroke experience is more with the smaller variety.
Had a straight six Mercury outboard where the bottom cylinder including plug became very clean after pumping water. But again probably different from this situAtion as the head triangular piece was rattling loose after I stopped.
The OP believes the engine ( cylinder) was running to get to this state.
At the risk of being a pain, you say also the engine needs to be running to get to this state , that that somewhat contradicts you saying that there could be spark but that does not mean there is burning.
Sometimes / oftentimes I question the science behind what is actually occurring to see problems from different angles. ( too lateral thinking).

[yammie15]

Thanks everyone for the support. Very much appreciated.

The head gasket is on order and expect arrival in two weeks. In the meantime, I know I need a couple of sheets of emery paper, and I have lined up a torque wrench. Anything else I may need? Gasket goo?

And someone mentioned some tips on working the bolts on the head loose without breakage. This is bound to be the BIG problem. Can you fill me in? What about removing the bolts when the engine is still hot? I need to complete the job in one day (hopefully), so need all the info upfront.

I have a service manual for an earlier model of the 15 horse. It specifies 12ft/pound for the head bolts. Can someone confirm that for the 15MSH model.

And the question of the exhaust divider plate has come up more than once. Is that something I can check once the head is off?

And finally, is there some follow-up maintenance procedure after the engine has run-in? Re-torquing the head comes to mind.

I'll photograph what I find on the inside, and post here.

Once again, thank you so much. You guys are great!
Bry
Luperon Harbor
Dominican Republic

[TownsendsFJR1300]

I would have a heat gun and some really good penetrating oil(I like PB Blaster).

You can start spraying those bolts, around the block, etc now. You may get better penetration brushing off the white corrosion with a small SS tooth brush. (You may open a leak too if its really bad so beware).

Work on a room temp block. Put heat as hot (as the heat gun goes) as possible around the BLOCK wherever you have a stuck bolt. Smacking the head of the bolt moderately can also break loose corrosion and a stuck bolt.

If it isn't moving with heat, smacking, do the same procedure again. If its absolutely stuck, FORCING IT WILL break off the bolt-NOT good....

To my knowledge, re-torquing isn't required. You can, don't loosen but "click" back to spec just for S&G's...Won't hurt anything.

Have a small SS brush handy to clean out the water jackets and head as you'll very likely find lots of white corrosion / salt in the head and water jackets...

[yammie15]

Thanks Townsends... still waiting on the head gasket.

Any further confirmation on the 12 ft/lbs torque on the headbolts? And is gasket goo a no-no?
Bry

[TownsendsFJR1300]

Thanks Townsends... still waiting on the head gasket.

Any further confirmation on the 12 ft/lbs torque on the headbolts? And is gasket goo a no-no?
Bry

Your welcome.

No head gasket sealer is used. Some gaskets go on one way only so pay close attention to the gasket/any markings, holes, etc...

IDK the exact torque on the head bolts.

Either the shop manual will state. (sometimes its actually imprinted in the head as is the order torque down) or someone needs to chime in.

Progressive torquing down (start lowish on all bolts, then work your way up eventually to full torque) is suggested.